In the television field, High Definition Multimedia Interface (HDMI), which is the successor to Digital Visual Interface (DVI) for video presentation, allows full uncompressed audio and video to be transmitted from a multimedia source, such as a disk player, to a TV over a single line. HDMI supports HD video formats (1080 p, etc.), and up to eight channels of audio at 192 KHz.
HDMI may be used in conjunction with High Definition Content Protection (HDCP), which is a security feature for preventing unauthorized hardware from connecting to authorized hardware and for transferring protected and encrypted data over a non-secure medium. In essence, HDCP uses a key exchange, and if a satisfactory key exchange is not effected, in some implementations including some DVD and Blu-Ray disk implementations, an “image restraint token” (IRT) on the disk can be set to prevent viewing the multimedia in full HD and to permit viewing the multimedia only in a lower resolution format, e.g., to a 960×540 pixel format or lower (720×480). Thus, when a player is connected to a display using HDMI with HDCP, indicating an authorized connection and resulting in a successful key exchange, the IRT flag on the disk will not result in a lower resolution display, and the high resolution format will be presented. It is only when a non-HDCP situation arises that the IRT flag causes a low resolution format to be displayed.
As recognized herein, an IRT can be used to permit selling a movie on a disk before an expiration date, with viewing of the movie being permitted only in lower resolution formats (in non-HDMI/HDCP systems) until the expiration date, at which time the IRT is reset to permit viewing the movie in full resolution. In this way, revenue can be realized prior to an intended expiration date, while preserving the value of the expiration date in terms of prohibiting hi-resolution viewing until then. However, the present invention also recognizes that a pirate might try to advance the date on the player to be the expiration date and to thereby prematurely play the high resolution version. With this in mind, the invention herein is provided.